This invention pertains to the art of robot structures designed to perform a pick and place function.
Among the current designs of assembly robots, there are two general types which are considered of interest in connection with this invention. One type is the fixed sequence, two-point pick and place robot which is basically limited to picking from one location and placing at another location. Such two-point robots have the advantages of being simple, accurate, of high speed and relatively low cost. The other type of robot is the fully position-programmable servo-controlled robot which can be programmed to pick and place in infinitely variable positions. The extreme flexibility of the servo-controlled robot is its principal advantage but it is much more complex, less accurate, of lower speed, and many times more expensive and difficult to maintain relative to the simple two-point pick and place robot.
One aim of this invention is to provide a pick and place robot which has most of the apparent advantages of the two-point pick and place arm with respect to accuracy, speed and cost, but is also adapted to be operated in a mode in which a multitude of pick and place locations are available so, in effect, the robot of the invention bridges the functional gap between the two types of pick and place robots. It is a further aim of the invention to provide a robot structure for pick and place service in which in most instances the path of the working tool is of a generally smooth arcual character to obtain the benefits of smooth acceleration and deceleration motions.